This application relates generally to a combined illumination and imaging system. More specifically, this application relates to an illumination and imaging system configured for use with a thermal substrate processing apparatus.
There are numerous examples of applications in which a substrate may be processed thermally, including thermal annealing processes and chemical-vapor-deposition processes, among others. A general structure of an apparatus that may be used for such thermal processes is illustrated schematically in FIG. 1A. The apparatus comprises an illumination system 104, a stage 128 adapted to receive a substrate 124, and a translation mechanism 132. The illumination system comprises 104 comprises an electromagnetic source 108 that produces illumination that is shaped by an optical arrangement 116 to generate a narrow elongated beam 120 as a line of radiation incident on the substrate 124.
The stage 128 may comprise a chuck or other mechanism for securely holding the substrate 124 during processing. For instance, a frictional, gravitational, mechanical, and/or electrical system may be provided for grasping the substrate 124. The translation mechanism 132 is configured to translate the stage 128 and the beam 120 relative to each other, through movement of the stage 128, movement of the illumination system 104, or movement of both. Any suitable translation mechanism may be used, including a conveyor system, rank-and-pinion system, or the like. The translation mechanism 132 is operated by a controller 136 to define the scan speed of the line of radiation relative to the stage 128.
A more detailed description of specific structures that may be used in implementing the thermal processing apparatus of FIG. 1A and of various alternative and equivalent variations to such a structure, is provided in published PCT application WO 03/089,184, the entire disclosure of which is incorporated herein by reference for all purposes.
FIG. 1B provides a top view of the substrate 124 overlying the stage 128. The line of radiation 140 provided by the narrow elongated beam 120 may extend across the entire diameter of the substrate 124. The relative geometry of the illumination system 104 and the translation mechanism 132 are such that the line of radiation 140 traverses the substrate 124 in a direction perpendicular to its length, i.e. the line 140 remains parallel to a fixed chord 144 of the substrate 124.
There are numerous considerations that may affect the effectiveness of such a system. This application describes embodiments of structures that may be used for the illumination system in such a thermal processing apparatus.